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      <title>FREQ2</title>
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      <div class="title_refTopic" id="xps10_pagetitle">FREQ2 </div>
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      <h4 class="refClassification">Frequency List, Alternate Form 2 </h4>
      <p class="para_refTopic">Defines a set of frequencies to be used in the solution of frequency response problems by specification of a starting frequency, final frequency, and the number of logarithmic increments desired. </p>
      <div class="title_refCategory">Format: </div>
      <div class="refCategoryContent">
         <table border="1" width="100%" align="center">
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               <col span="1" width="10*">
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                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">1 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">2 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">3 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">4 </p>
                  </th>
                  <th align="center" colspan="1" rowspan="1">
                     <p class="para_th">5 </p>
                  </th>
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                     <p class="para_th">6 </p>
                  </th>
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                     <p class="para_th">7 </p>
                  </th>
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                     <p class="para_th">8 </p>
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                     <p class="para_th">9 </p>
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                     <p class="para_th">10 </p>
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            </thead>
            <tbody>
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                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">FREQ2 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">SID </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">F1 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">F2 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">NF </p>
                  </td>
                  <td align="center" bgcolor="gray" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" bgcolor="gray" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
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                  <td align="center" bgcolor="gray" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" bgcolor="gray" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" bgcolor="gray" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
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         </table><br></div>
      <div class="title_refCategory">Example: </div>
      <div class="refCategoryContent">
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            <tbody>
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                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">FREQ2 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">6 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">1.0 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">8.0 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">6 </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
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                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
                  <td align="center" colspan="1" rowspan="1">
                     <p class="para_td">&nbsp; </p>
                  </td>
               </tr>
            </tbody>
         </table><br></div>
      <div class="title_refCategory">Fields:</div>
      <div class="refCategoryContent">
         <table cellpadding="9" width="100%" align="center">
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                     <p class="para_th"><b class="uiTerm">Field </b></p>
                  </th>
                  <th align="left" colspan="1" rowspan="1">
                     <p class="para_th"><b class="uiTerm">Contents </b></p>
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            </thead>
            <tbody>
               <tr>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">SID </p>
                  </td>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">Set identification number.  (Integer &gt; 0) </p>
                  </td>
               </tr>
               <tr>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">F1 </p>
                  </td>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">First frequency.  (Real &gt; 0.0) </p>
                  </td>
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                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">F2 </p>
                  </td>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">Last frequency.  (Real &gt; 0.0, F2 &gt; F1) </p>
                  </td>
               </tr>
               <tr>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">NF </p>
                  </td>
                  <td align="left" colspan="1" rowspan="1" valign="top">
                     <p class="para_td">Number of logarithmic intervals.  (Integer &gt; 0; Default = 1) </p>
                  </td>
               </tr>
            </tbody>
         </table><br></div>
      <div class="title_refCategory">Remarks: </div>
      <div class="refCategoryContent">
         <ol type="1" start="1">
            <li>
               <p class="para_item">FREQ2 entries must be selected with the Case Control command FREQUENCY = SID. </p>
            </li>
            <li>
               <p class="para_item">The units for F1 and F2 are cycles per unit time. </p>
            </li>
            <li>
               <p class="para_item">The frequencies defined by this entry are given by </p>
               <p class="para_item"><img align="bottom" src="graphics/bulkfgil-equ10.gif" border="0"></p>
               <p class="para_item">where </p>
               <p class="para_item"><img align="bottom" src="graphics/bulkfgil-equ11.gif" border="0"> 
               </p>
               <p class="para_item">and <em>i</em> = 1, 2, ..., (<em>NF</em>+1) 
               </p>
               <p class="para_item">In the example above, the list of frequencies will be 1.0, 1.4142, 2.0, 2.8284, 4.0, 5.6569 and 8.0 cycles per unit time. </p>
            </li>
            <li>
               <p class="para_item">All FREQi entries with the same frequency set identification numbers will be used.  Duplicate frequencies will be ignored. <em>f<sub class="subscript">N</sub></em> and <em>f</em><sub class="subscript"><em>N</em>−1</sub> are considered duplicated if 
               </p>
               <p class="para_item"><img align="bottom" src="graphics/bulkfgil-equ12.gif" border="0"></p>
               <p class="para_item">where DFREQ is a user parameter, with a default of 10<sup class="superscript">−5</sup>.  <em>f<sub class="subscript">MAX</sub></em> and <em>f<sub class="subscript">MIN</sub></em> are the maximum and minimum excitation frequencies of the combined FREQi entries. 
               </p>
            </li>
            <li>
               <p class="para_item">In modal analysis, solutions for modal DOFs from rigid body modes at zero excitation frequencies may be discarded.  Solutions for nonzero modes are retained. </p>
            </li>
         </ol>
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